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Glass ceilings still abound, but in the music industry, a group of young women are busting it down.

On our list of the 10 highest-paid celebrities under 30, women take six spots, and four of the top five, led by Taylor Swift at No. 1. We estimate that between May 2011 and May 2012, Swift earned $57 million. Each of the 22-year-old singer’s three albums have gone platinum at least four times, meaning that in these days of waning music sales, Swift can be counted on to sell at least 4 million copies of every album.

Then there’s her concerts, which bring in an average of $1 million per night, and her endorsement work for products like CoverGirl makeup. Swift’s money and fame helped her land in 11th place on our annual Celebrity 100 list this year, which is based on earnings and metrics we’ve developed to quantify buzz.

Another young woman who is making a killing in music is Rihanna. The Barbados-born singer earned an estimated $53 million between May 2011 and May 2012, putting her in third place on the list. Her earnings this year got a big boost from an 85-night tour and her 2011 hit album Talk That Talk, which has gone gold in the U.S. and launched hits like “We Found Love.”

Like Swift, Rihanna also earns big money from endorsements. She happily promotes Vita Coco coconut water and Nivea lotion. Rihanna debuted on the Celebrity 100 this year in fourth place.

To determine who the highest-paid celebrities under 30 are, we considered album and concert sales, movie paydays, profit participation, endorsements and advertising work. We talked to managers, agents, lawyers and other in-the-know folks to come up with our estimates. We did not deduct for agent fees or the expenses related to being a celebrity. We did not include athletes on this year’s list, although they are included in the Celebrity 100.

The highest-ranking man on our list isn’t even old enough to drink. Just 18 years old, Justin Bieber comes in a close second behind Swift with $55 million in earnings. Bieber (who appeared on the cover of our Celebrity 100 issue this year) earns big from his music sales, concerts and endorsements for products like Proactiv. The Bieb is also a budding venture capitalist: He’s made investments in start-up companies like Stamped, Tinychat and Spotify.

Bieber is the only male in the top five. Ranking fourth is Lady Gaga, who at 26 earned $52 million between May 2011 and May 2012. That’s a big drop from the $90 million she earned to top our under-30 list last year. That’s because our time frame ended before the singer embarked on her latest world tour, which is selling out shows in Eastern Europe. Expect the pop princess to earn more next year.

Rounding out the top 5 is Katy Perry. The singer earned an estimated $45 million this year. At the age of 27 she is now a divorced millionaire. Her heartache helped power some of her new hits, including “Part of Me,” which has gone platinum in the U.S. Perry ranked eighth on the Celebrity 100, but her popularity didn’t help her recent concert film at the box office. Katy Perry: Part of Me earned only $7 million in its opening weekend.

i'm impressed that she's at number 4 without having any big endorsement deals (i.e., coconut water, covergirl, proactiv lol) like the other three. all i can think that she's does is the viva glam mac campaign for charity, and idk if that counts for this period.